Cast metal.



UNITED sTA'rns ROBERT C. TOTTEN, PITTSBURG, PENNSYLVANIA.

cAs'r METAL.

No Drawing. Application filed May 19,

Specification of Letters Yatent. Patented J an, 25, 1910.

1909. Serial No. 497,107.

To all whom it may concern:

Be it known that 1, ROBERT C. To'r'rnn, a resident of littsburg, in the county of Allegheny and State of Pennsylvania, have inrented a new and useful Improvement in Cast Metal; and I do hereby declare the fol lowing to be a full, clear, and exact description thereof.

My invention relates to a new composition of cast metal, its object being to provide a casting metal for the production of chill castings, such as car Wheels, chill rolls and the like and to produce castings of great strength of body and hard wearing surface without the employment of chilling cast iron or by the employment of a relatively'small proportion thereof. 1

It consists, generally stated, in a composition of casting metal containing cast iron, nickel and a chromium compound containing combined iron and carbon such as ferro chrome; the nickel increasing the strength and controlling the depth of chill in the cast iron while the chromium compound .increases the hardness of the surface formed and provides combined carbon and iron which furnishes the necessary combined carbon to produce the chill, or reduces the proportion of chilling cast iron necessary to be used in the casting metal, the result being a casting metal having great strength of body and high wearing properties. I

In the employment of the invention I use principally iron smelted by the use of coke or coal and Which contains a large proportion of graphit-ic carbon and only a very small proportion, sometimes only a trace, of

combined carbon. I also employ nickel and ferro chrome or like chromium compound containing iron, the ferro chrome usually containing a large proportion of combined carbon, ranging as high as 10 to 12 per cent. I also employ nickel in suitable proportion, it being preferred that the chromium present shall be about 30/100 (.30) to about 70/100 (.70) per cent. of nickel in the mixture. I may also employ a chilling cast iron either in pig metal form or in the form of old car wheels and Where the same is employed the proportion of nickel employed varies according to the depth of chill to be produced and the proportion of old car wheels in the casting metal and the increased strength to be given to the casting, as the nickel increases the tensilestrength of the metal and also acts to decrease the depth of chill and where such old'car wheels areemployed, which'are liable to form a deep chill, by increasing the proportion of nickel, the depth of the chill canbe regulated.

tion as'it is employed a greater quantity of ordinary'coke' or coal iron may be employed, the chrome furnishing the'combined carbon to give chilling qualities to the metal. For

add to the'strength of the casting metal, the proportlon of steel also depending uponthe amount of chilling cast iron used in the castas desired according to the character of the in the casting and thedepth of chill rebined in an desired way, the coke or coal iron, the chllling cast ironand steel, if the same are used, being melted in the cupola or like furnace with the ferro chrome and nickel, or the ferro chrome and nickel may be formed as an alloy, a suitable proportion of cast iron being used with the same, and the resultant alloy be melted in the furnace with the other metals or be introduced in the 'molten metal before the casting is formed, or the ferro chrome and nickel may be introduced separately. The casting metal, so formed is of very high tensile strength duced by both the combined carbon in the relatively small proportion thereof.

lVhat I claim is:

1. A new composition of chilling cast metal containing cast iron, nickel and a chromium compound containing combined iron and carbon.

2. A new composition of chilling cast metal containing coke or coal iron, nickel and a chromium compound. containing combined iron and carbon.

metal containing chilling cast iron, coke or containing combined iron and carbon.

some purposes I may also employ steel'to 'ing metal. The several metals can be varied.

quired. .The several metals may be com and has a very hard wearing surface pro- 4. A new composition of chilling cast" metal to be produced, the desired strength 3. A new composition of chilling cast p coal iron, nickel and a chromlum compound 60 3 The ferro chrome provides a large pro- V port on of combmed carbon, and in proper- 90 metal and the chromium present therein and these results are obtained either without thev presence of any chilling cast ll'OIl or with a I metal containing chilling cast iron, coke or coal. iron, steel, nickel and chromium compound containing combined iron and carbon. 5. A new composition -of casting metal 5 containing coke or coal iron, steel, nickel and a chromium compound containing combined iron and carbon.

6. A new composition of chilling cast and ferro chrome.

In testimony wher'eof, I the said Ronnn'r C. ToT'rEN, have hereunto set my hand.

ROBERT C. Witnesses G. H. RANKIN, JOHN F. WILL.

,TOTTEN. 

